Jim, that is a heck of a toy... if you can keep the motivation to do the work, you can lose some weight with it, but more importantly you can increase cardio strength that really is the key to health. It's a great way to do thing.
I have been losing so far just by cutting back on snacks, extras, and eating more reasonably. I a few days I might actually add some exercise just to push the number along.
This page is interesting:
http://www.freedieting.com/tools/calories_burned.htm
It is important to note that 15 minutes of aerobics barely burns the calories in the yogurt I am eating right now. that isn't very much ;-)
Alex